The present invention relates to an improved folding structure for folding chairs and particularly a folding structure for reducing the size of folding chairs.
A conventional folding chair such as the one shown in FIGS. 1, 2 and 3 generally includes a seat bracket, a backrest bracket pivotally engaging with the rear end of the seat bracket, and front legs and rear legs located at two sides of the seat bracket, and two armrests pivotally mounted to the top ends of the front and rear legs. For folding the chair, first, move a safety latch mounted on the rear leg upwards to disengage the safety latch from a pivotal lever, then apply force on the backrest bracket and seat bracket to move the two folding towards each other. The front legs will be moved about the pivotal joints where the seat bracket and armrest engaged and move towards the rear legs. The backrest bracket having formed a toggle joint relationship with the seat bracket through the pivotal lever which has one end engaged with a shaft pivotally fastened to one side of the rear leg, will be swung relative to the rear leg and moved towards the rear leg. The seat bracket will be driven by the backrest bracket and move toward the backrest bracket such that both the seat bracket and backrest bracket will be juxtaposed between the front and rear legs. The folding chair thus may be folded and reduced to a smaller size to facilitate transportation and storing. However, the folding mechanism set forth above still have drawbacks, notably:
1. In order to make the seat bracket and backrest bracket moving and folding simultaneously, the seat bracket has to extend an extra rear section to engage with the pivotal lever. The extra rear section of the seat bracket cannot seat people when the chair is extended. It becomes a waste and increases costs without adding benefits.
2. The pivotal lever is an integrated two-piece element with a shaft running through the rear leg. The interval of the two-piece element forms a swing space for the backrest bracket. The two-piece element further has an integral head attached to the rear leg for latching the safety latch. After the chair is folded, the head of the pivotal lever is extended outwards and often result in piercing through the package cartons or scratch the surrounding goods. To prevent this from happening, the package cartons have to be made larger. This increases the shipping size and transportation costs. It also takes more storage space. The jutting head of the pivotal lever also tends to injure people, particularly children, when extended for use. It is not a safe design and still has rooms for improvement.
The primary object of the invention is to resolve the foregoing disadvantages. The invention provides an improved folding structure that has a smoother profile when folded and does not have jutting object, thus can greatly reduce the folding size. The folding structure of the invention includes a pivotal lever to link the backrest bracket and the rear legs. The backrest bracket has a cradle hub with a flange extending towards the rear leg. The pivotal lever has one end attached to a shaft pivotally engaging with the rear leg. The shaft may function as a fulcrum when the chair is folding to allow the backrest bracket and rear legs to extend or fold pivotally. The flange may rest on the rear leg at different spots when the chair is extended for use or folded. Hence the folding chair may be shrunk to a much smaller size.